Was IRIDIUM ever found as a residue in ALABASTER
or AGATE or CALCIUM from VOLTERRA, ITALY?

Question Date: 2014-01-23

Answer 1:

The answer is unlikely. All of our iridium comes
from meteorites, because any iridium that was in
the Earth sunk to the bottom because it's so
heavy, so there's nothing in the crust.

Answer 2:

Iridium was found in a site in Italy at the
Cretaceous-Tertiary boundary layer, and was used
as one piece of evidence for a meteoritic
mechanism for the mass extinction that coincides
with that boundary.